You can start modeling without any reference, however, if you model on top of a turnaround reference sheet, the final result would be better, it also ease the progress of modeling.
The recommended features for reference sheet in Dust3D:

Only one image, but include at least two profiles in the image, one for front view, one for side view. And align horizontally with the same height.

Image size less than 1MB. Because if you save the document, the reference image will also be included in the .ds3 file.

No blur filter, make a clean sheet, Dust3D will blur it for you when you load the image.